This invention relates to sprinkler systems for protecting the contents of metal buildings against fires.
Conventional metal building fire protection systems have sprinklers mounted on pipes which are supported from purlins that extend between the roof support beams, or rafters, of the building. The rafters are spaced about 25 feet apart to form a plurality of bays and normally two or more sprinkler lines are supported from the purlins extending across the rafters at about 5-foot intervals over each bay. Because of the weight of the sprinkler lines and the water contained in them, the purlins, which have a Z-shaped cross-section, must be made strong enough to support the sprinkler lines as well as the roofing over the bay, which increases construction costs. In addition, since standard clamp-type hangers can not readily be installed on the purlins because of their Z-shape, it is necessary to drill or punch holes in the purlins for hanger installation, further increasing the installation costs.
The Meyer et al. U.S. Pat. No. 5,366,022 discloses extended coverage pendent and upright ceiling-mounted sprinklers for protecting areas up to 256 square feet per sprinkler and potentially up to 400 square feet per sprinkler.
The patent to Polan et al. U.S. Pat. No. 5,669,449 discloses sprinkler systems having pipes supported from the beams of a pitched roof with upright sprinklers spaced up to 20 feet apart having deflectors with horizontal central portions and downwardly inclined side portions to deflect upwardly directed water over an area of up to 225 square feet to be protected by each sprinkler.
The Mears U.S. Pat. No. 4,296,815, the Fischer U.S. Pat. No. 4,296,816, the Galaszewski U.S. Pat. No. 4,987,957, the Fries U.S. Pat. No. 5,722,599 and the Bosio et al. U.S. Pat. No. 5,727,737 disclose horizontal side wall sprinklers provided with deflectors having a vertical portion in line with the outlet orifice of the sprinkler and a generally horizontal deflector portion disposed above the vertical portion to distribute water over areas to be protected which extend laterally on one side of the location of the sprinkler.
The Tramm U.S. Pat. No. 5,810,263 discloses a horizontal sprinkler provided with a deflector having a vertical portion in line with the sprinkler orifice and a generally horizontal portion extending rearwardly from the vertical portion toward the sprinkler orifice and having downwardly inclined side portions to confine the water distributed from the sprinkler to a desired area laterally beneath the sprinkler.